<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://cdn.staticfile.org/jquery/3.2.1/jquery.min.js"></script>
    <style>
        div{
            padding: 20px;
            border: 1px solid #000;
            position: relative;
        }
        main{
            height: 1000px;
        }
    </style>
</head>
<body>
    <div>
        <a href="">这是a</a>
    </div>
    <main></main>
    <script>
    //    var w = $("a").width();
       console.log($("div").width()); //content
       console.log($("div").innerWidth()); //content+padding
       console.log($("div").outerWidth()); //content+padding +border

    //   获取到文档的距离
       console.log($("a").offset());
    //    获取到最近的设置有非静态定位属性的父级标签的位置
       console.log($("a").position());
    </script>
</body>
</html>